Octagonal

an octaganal object is defined as one which has a octagon for a cross section.

as a reference to nunchaku you get two main types of handle, one of which is octaganal. this is traditional of the Okinawan style, while the chinesse style has a circular cross section.

one purpose of the octagonal handle is you have several points which can be used more effectivly in blows or strikes since the pressure can be applied to a smaller surface area.